Subject: Here are the CA standards.
I always advocate that a person working on prevention, obtain a Snellen (visual acuity) chart, set it up with a bright light on it -- and read it.
I always advocate that you understand the line you explicitly must pass. Here are the California requirements -- but the closely match the other states. Obviously, in time, by using the plus, you would want to slowly clear the 20/25 to 20/20 line. For comparison, the FAA 3rd class license, requires that you have 20/40 (or better) in each eye. I you are seeing 20/50, you should consider the "target" as exceeding the 20/40 line. Always be safe, and always be legal. For personal self confidence I advocate you get two $9 test lenses (-1/2 and -1) to confirm your refractive state yourself -- so you know your eye is capable of 20/20 vision -- before you start wearing a plus to change your refractive state from -3/4 diopters to 0.0 diopters (necessary to pass the 20/20 line.
DMV's Vision Screening Standards
DMV is authorized to test all applicants’ vision under California
Vehicle Code (CVC §12804.9(a)(1)(E) ).
Anyone who applies for an original or renewal driver license must meet
the department’s visual acuity (vision) screening standard. DMV’s
vision screening standard is:
20/40 with both eyes tested together and
20/40 in one eye and
20/70, at least, in the other eye
Minimum Visual Acuity Requirement
If you cannot meet the vision screening standard, you must have a minimum visual acuity in at least one eye better than 20/200 (best corrected). Visual acuity is a person’s ability to see items clearly and sharply and to recognize small details. You may wear glasses or contact lenses to meet the minimum visual acuity standard but you cannot wear a bioptic telescopic or similar lens. DMV can not license drivers who do not meet the minimum visual acuity standard.